The coastal edge of the Northeast Water polynya in spring 1993

Multidisciplinary, marine ecological observations were conducted at the shallow water edge of the Northeast Water in June, 1993. Although variable in size and shape, a small polynya was constantly present at Eskimonaes, at the fast-ice edge of Ingolfsfjord. A shallow stratified layer developed at the water sufface at negative water and air temperatures—an effect of sea ice melting in cold water early in the season. Nutrients were recorded in considerable quantities, although by mid July NO₃ had become depleted. The chlorophyll and phytoplankton maxima at 8–12 m depth had peak values of 2 mg chl a m⁻³, typical for Arctic algal blooms. The phytoplankton included over 90 species and was dominated by the Fragillariopsis group. Zooplankton was poor in biomass and density, but over 23 taxa were found, with the copepods Oithona similis and Pseudocalanus acuspes being numerically dominant. Sedimentation was approximately 0.2 g dry weight m⁻² d⁻¹ and suspended matter concentrations ranged from 4 to 19 mg l⁻¹. The benthos was represented by hard bottom forms only, with a surprisingly dense cover of macrophytes. Juvenile sea urchins (Strongylocentrotus droebachiensis), brittle stars (Ophiocten sericeum) and amphipods were dominant. Higher trophic levels were represented by benthic feeders, such as eiders and walruses. The area observed was more similar to high Arctic fjord ecosystems than to the offshore central Northeast Water polynya.     

护坡结构在Mirsarai海岸防护工程中的应用

传统的混凝土或生态型护坡结构均不能兼顾海岸防护对结构防浪消能、耐久性、生态性的需求。针对孟加拉Mirsarai海岸防护工程特点，并经方案比选，采用混凝土块体与生态组合型护坡结构，对其技术质量重难点、典型施工问题、基槽镇脚棱体和坡面块体的防浪稳定性、生态护坡与结构排水进行分析。结果表明，基槽与坡面块体稳定质量满足防浪要求，能够有效抵御汛期海浪冲击；植被生态型护坡利用根系加固土层，控制土粒及下部材料冲刷流失，并兼具生态与景观作用。     

沉箱开孔对平均越浪量的影响

针对开孔沉箱对平均越浪量影响的问题,以国内某港区通用码头工程为基础,对比分析了直立式沉箱和开孔沉箱平均越浪量的多种经验公式计算方法,并和断面物理模型试验结果进行比较。公式计算结果显示,开孔沉箱与不开孔沉箱平均越浪量之比为25%~50%;断面物理模型试验结果显示,沉箱开孔与不开孔时越浪量之比为30%~82%。研究表明开孔沉箱能够有效降低海岸结构物的平均越浪量;国内学者提出的开孔沉箱越浪量计算方法所得结果更加接近物理模型试验结果。     

塑性混凝土咬合桩在临海基坑工程中的应用

以蛇口邮轮中心基坑支护工程为例,研究在临海抛石地基上基坑支护方案的选用。通过现场试验获取施工参数并计算渗透系数,根据结果选择塑性混凝土咬合桩结构方案。介绍塑性混凝土咬合桩的受力特点和计算方法,以及在止水帷幕中的应用,并与实测资料相验证,证明了在抛石地基临海基坑中采用塑性混凝土咬合桩是安全可行的。     

Shaping the Coast with Permits: Making the State Regulatory Permitting Process Transparent with Text Mining

This paper examines the California Coastal Commission's permitting process. Using several text mining techniques, including web scraping, information extraction, and supervised classification, I demonstrate how to retrieve empirical data from unstructured texts, namely public meeting agendas and staff reports. Contrary to the concern that the Commission routinely delays or rejects permitting requests, the data reveal that outright rejection of permit applications is rare. On average, eight of ten applications were approved. Single-family homes and commercial development projects were approved about 80% of the time; the rates were about 70% for seawalls and retaining walls, and 60% for land-use changes. Most applications were processed swiftly, with a median application length of 3 months. The agency's influence comes primarily from negotiating each application. Qualitative study of 50 cases pertaining to single-family home construction reveals that the agency adopts a “managed development” approach, that is, allowing development but scrupulously managing various aspects of development. These case studies illustrate how the agency interprets the broad, abstract state laws and translates the mandates into enforceable actions as permitting conditions. In areas where the state mandates conflict, particularly over development in receding shorelines, the agency has the largest leverage in creating and implementing its preferred policies. The text mining techniques demonstrated in this paper can be applied to study any governmental agency. These techniques help to extract information from a massive volume of papers and organize them into a database for analyses. The empirical data extracted from texts can significantly increase bureaucratic transparency.     

Adapting without Retreating: Responses to Shoreline Change on an Inlet-Associated Coastal Beach

Coastal barrier systems around the world are experiencing higher rates of flooding and shoreline erosion. Property owners on barriers have made significant financial investments in physical protections that shield their nearby properties from these hazards, constituting a type of adaptation to shoreline change. Factors that contribute to adaptation on Plum Island, a developed beach and dune system on the North Shore of Massachusetts, are investigated here. Plum Island experiences patterns of shoreline change that may be representative of many inlet-associated beaches, encompassing an equivocal and dynamically shifting mix of erosion and accretion. In the face of episodic floods and fleeting erosive events, and driven by a combination of strong northeast storms and cycles of erosion and accretion, the value of the average Plum Island residence increases by 34% for properties on the oceanfront where protection comprises a publicly constructed soft structure. Even in the face of state policies that ostensibly discourage physical protection as a means of adaptation, coastal communities face significant political and financial pressures to maintain existing protective structures or to allow contiguous groups of property owners to build new ones through collective action. These factors mitigate against adapting to shoreline change by retreating from the coast, thereby potentially increasing the adverse effects of coastal hazards.     

Obsolete Maps and Coastal Management: Case Studies from Northwest Ireland

On dynamic coastal sites, subject to rapid and sometimes unpredictable shoreline changes, management problems can be aggravated if legally authoritative maps are obsolete. These difficulties are illustrated by two case studies from County Donegal in northwest Ireland. The first case study outlines the problems that arise where statutory functional area boundaries are based on a near century-old map. The second case study deals with the problems of planning development on a site where a customized map only a few years old has been rendered obsolete by rapid coastal erosion. Other problems are caused by the inappropriate use of maps. Suggestions are made to mitigate the effects of outdated maps.     

客运专线抗台风措施研究

客运专线高速车辆轻量化,使其抗强风能力减弱。为保证客运专线安全运输,从线路、路基、桥梁、隧道、站场及电气化设施等方面提出抗台风的设计原则,可采用的运输安全监控预警及运营安全措施。以上研究成果可确保沿海铁路的运营安全,进一步提高沿海铁路建设质量。     

基于仿真的沿海港口甩挂场站布局方案比选

甩挂运输以其高效低碳的特点正得到迅速发展。针对当前国内甩挂场站研究中功能布局、建设规模等方面的量化研究相对不足,利用微观仿真软件VISSIM建立沿海港口甩挂运输场站交通仿真模型,研究甩挂车辆在场站内运行状况,评价场站内部功能布局方案,并以某港口为例,验证该模型的有效性。     

Challenges and Benefits in the Design of Coastal Walking and Cycling Amenities: Toward a More Integrated Coastal Management Approach

The planning and development of pedestrian and cycling amenities in coastal urban environments is a challenging process because a wide range of policies and considerations must be taken into account. Among these, the concepts of sustainability and more recently, resilience, have been gaining prominence. Green Infrastructure design approaches can integrate aspects of both sustainability and resilience, providing multiple services within single development projects. This study focuses on Dublin and examines a range of amenity projects at various stages of development that relate to the provision of new coastal walking and/or cycle routes. These are initially contextualized at the city level before focusing specifically on challenges and benefits associated with the design and implementation of such projects. Based on our findings, recommendations are made for optimizing the potential of future projects to effectively integrate with other initiatives so as to deliver broader policy objectives. A simple sequential model is presented that should assist developers and decision-makers to take a more integrated, multidisciplinary approach to meeting policy goals when planning and developing coastal amenities. Finally, this is remodeled into a set of considerations that are generally applicable to coastal development proposals of significant scale.